How Do You Calculate the Sun's Mass Using Mars' Orbital Data?

[Techcom0]

Mars travels around the Sun in 1.68 Earth years in an approximately circular orbit with a radius of 2.18 x 10^8 km. Determine the mass of the Sun.

Fairly easy, I know most of how to do it but I keep getting wrong answers. Help me out a bit? Thanks!

 

[homevolend]

Ok well you can you can set Fg equal to Fc.

Fg = Fc

G m_sm_m/r² = m_m4π²r/T²

Simplifies to

G M_s = 4π²r³/T²

So

(6.67x10^-11) M_s = 4(3.14)²(2.18x10¹¹)³/(52980480)²

M_s = UDOIT kg